Process for the production of an optical element from glass

ABSTRACT

The present disclosure relates to a method for producing an optical element ( 202 ), wherein a blank of transparent material is heated and/or provided and, after heating and/or after being provided between a first mold (UF) and at least one second mold (OF), is press molded to form the optical element ( 202 ), in particular on both sides, and is then sprayed with a surface treatment agent.

PRIORITY CLAIM

The application claims the priority of the German patent application DE10 2020 132 239.9, filed on 3 Dec. 2020, which is expressly incorporatedby reference in its entirety.

FIELD OF THE INVENTION

The invention relates to a method for producing an optical element orheadlight lens, wherein a blank made of glass or soda-lime glass isheated and/or provided and, after being heated and/or provided, ispress-molded between a first mold and at least one second mold to formthe optical element or headlight lens.

BACKGROUND

Press-molding methods are described in WO 2019/072325 A1 and WO2019/072326 A1, for example.

In addition to particular contour accuracy and precise opticalproperties being required, the desire has developed for moldingheadlight lenses from borosilicate glass or glass systems similar toborosilicate glass, in order to obtain increased weather resistanceand/or hydrolytic resistance (chemical resistance). Standards orevaluations methods for hydrolytic resistance (chemical resistance) arethe Hella N67057 standard test and the climatic test/humidity-frosttest, for example. High hydrolytic resistance is also classified as type1, for example. In the light of the requirement for borosilicate-glassheadlight lenses having corresponding hydrolytic resistance, the problemis posed of pressing headlight lenses from borosilicate glass or similarglass systems having the same hydrolytic resistance (chemicalresistance). In a departure from this problem, an alternative method forproducing an optical element or headlight lens from non-borosilicateglass and/or soda-lime glass is proposed.

U.S. Pat. No. 7,798,688 B2 discloses a projection headlight comprising aheadlight lens and a light source, wherein a surface intended to faceaway from the light source of the projection headlight comprises a layerwhich has an aluminum concentration that is greater than an aluminumconcentration inside the headlight lens.

DE 10 2006 034 431 A1 discloses a method for the surface-finishing ofalkali-comprising glass, wherein hot surfaces are brought into contactwith aluminum-chloride compounds from the vapour phase. According to DE10 2006 034 431 A1, bringing the hot glass surfaces into contact withaluminum chloride dissolved in organic solvent, e.g. in methanol,results in improved surface properties. It is advantageous here for thecontact between the glass surfaces and aluminum-chloride compounds fromthe vapour phase to take place at a reduced oxygen partial pressure. Bycontrast with the treatment from the vapour phase, in aqueousaluminum-chloride solutions, when in contact with a hot glass surface,high amounts of energy could be drawn from the glass surface in a shorttime due to the evaporation heat of the water on the glass surface,wherein side effects that occur, such as a reduction in strength andstrain-induced damage to the surface, would result in unacceptableproperties. In addition, organic solvents for aluminum chloride, such asmethanol or ethanol, would be ruled out by a person skilled in the art,since they would considerably reduce the oxygen partial pressure due totheir combustion, but oxygen would be required for incorporating thealuminum in the glass surface. In a departure from this knowledge,bringing the hot glass surface into contact with aluminum chloridedissolved in organic solvent, e.g. methanol, results in improved surfaceproperties.

Compared with the surface treatment described in DE 10 2006 034 431 A1for bottles comprising aluminum chloride and its solution in methanol,the teaching in EP 2 043 962 B1 sets out the need for a more durablesurface when producing flat glass in a more efficient manner. This needis met in EP 2 043 962 B1 in that, when producing soda-lime-silica-basedglass, the glass strip formed from the melt is transferred to anannealing furnace, wherein, before the annealing furnace, aluminumchloride is applied to the main surface of the glass strip at atemperature of between 540° C. and 850° C. by applying a mixture ofAlCl₃ and at least one solvent to the surface of the glass strip,wherein the mixture comprises 5-10% aluminum chloride and the solventcomprises ethanol.

SUMMARY

The disclosure relates to a method for producing an optical element orheadlight lens, wherein a blank made of glass or soda-lime glass isheated and/or provided and, after being heated and/or provided, ispress-molded between a first mold and at least one second mold to formthe optical element or headlight lens. In this case, it is provided thatthe optical element or headlight lens is sprayed with a spray mist,which is generated by means of a surface-treatment agent, comprising asolid dissolved in a solvent, and a gas.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a device for producing motor-vehicleheadlight lenses or lens-like free-forms for motor-vehicle headlights oroptical elements made of glass;

FIG. 1A is a schematic view of a device for producing gobs or opticalelements made of glass;

FIG. 1B is a schematic view of a device for producing motor-vehicleheadlight lenses or lens-like free-forms for motor-vehicle headlights oroptical elements made of glass;

FIG. 2A shows an exemplary sequence of a method for producingmotor-vehicle headlight lenses or lens-like free-forms for amotor-vehicle headlight or optical elements made of glass;

FIG. 2B shows an alternative sequence of a method for producingmotor-vehicle headlight lenses or lens-like free-forms for amotor-vehicle headlight or optical elements made of glass;

FIG. 3 shows an embodiment of a lance;

FIG. 4 shows another embodiment of a lance;

FIG. 5 shows an exemplary preform before entering a temperature-controlapparatus;

FIG. 6 shows an exemplary preform having a reversed temperature gradientafter leaving a temperature-control apparatus;

FIG. 7 shows an embodiment of a transport element;

FIG. 8 shows an embodiment of a heating device for a transport elementaccording to FIG. 7 ;

FIG. 9 shows an embodiment for removing a transport element according toFIG. 7 from a heating station according to FIG. 8 ;

FIG. 10 shows a headlight lens on a transport element according to FIG.7 ;

FIG. 11 shows another embodiment of a transport element;

FIG. 12 is a cross section through the transport element according toFIG. 11 ;

FIG. 13 is a schematic view of an embodiment of an annealing kiln;

FIG. 14 shows a lance according to FIG. 3 in a hood-type annealingfurnace comprising a protective cover for heating a gob;

FIG. 15 is a view of the hood-type annealing furnace according to FIG.14 from below;

FIG. 16 is a cross section through the protective cover according toFIG. 14 ;

FIG. 17 is a view into the interior of the protective cover according toFIG. 14 ;

FIG. 18 is a perspective view of the protective cover according to FIG.14 ;

FIG. 19 is a cross section through another protective cover;

FIG. 20 is a view into the interior of the protective cover according toFIG. 19 ;

FIG. 21 is a cross section through another protective cover;

FIG. 22 is a view into the interior of the protective cover according toFIG. 21 ;

FIG. 23 is a perspective view of the protective cover according to FIG.21 ;

FIG. 24 is a schematic view of a pressing station for pressing aheadlight lens from a heated blank;

FIG. 25 shows another embodiment of a pressing station;

FIG. 26 shows a detail of a pressing station;

FIG. 27 is a schematic view of a pressing station, modified with respectto the pressing station according to FIG. 24 , for pressing a headlightlens from a heated blank;

FIG. 28 is a view of a detail of the pressing station according to FIG.27 ;

FIG. 29 is a schematic view for explaining tilting and radial offsetrelative to the upper mold;

FIG. 30 is a schematic view for explaining tilting and radial offsetrelative to the lower mold;

FIG. 31 shows an embodiment of a decoupling element for torsion;

FIG. 32 shows an embodiment of a modification of the pressing stationaccording to FIGS. 24, 25, 26, 27 and 28 for pressing under vacuum ornear vacuum or negative pressure, explained on the basis of a modifiedrepresentation of the schematic view according to FIG. 24 ;

FIG. 33 is a cross-sectional view of an embodiment of asurface-treatment station;

FIG. 34 is a schematic view of a motor-vehicle headlight (projectionheadlight) comprising a headlight lens;

FIG. 35 is a view of a headlight lens according to FIG. 34 from below;

FIG. 36 is a cross section through the lens according to FIG. 35 ;

FIG. 37 is a detail of the view according to FIG. 36 ;

FIG. 38 shows the detail according to FIG. 37 with a detail of thetransport element (in cross section);

FIG. 39 is a schematic view of an embodiment of a vehicle headlightaccording to FIG. 1 ;

FIG. 40 shows an embodiment of matrix light or adaptive high beam;

FIG. 41 shows another embodiment of matrix light or adaptive high beam;

FIG. 42 shows an embodiment of an illumination device of a vehicleheadlight according to FIG. 39 ;

FIG. 43 is a side view of an embodiment of a front optics array;

FIG. 44 is a plan view of the front optics array according to FIG. 43 ;

FIG. 45 shows the use of a front optics array according to FIGS. 43 and44 in a motor-vehicle headlight;

FIG. 46 shows another embodiment of an alternative vehicle headlight;

FIG. 47 shows another embodiment of an alternative vehicle headlight;

FIG. 48 shows an example of the illumination by means of a headlightaccording to FIG. 47 ;

FIG. 49 shows an embodiment of superimposed illumination by means of theillumination according to FIG. 48 and the illumination by two otherheadlight systems or sub-systems;

FIG. 50 shows an embodiment of an objective lens;

FIG. 51 shows luminous power plotted logarithmically against thedistance from a considered point of an object;

FIG. 52 shows a projection display comprising a microlens array having acurved base surface;

FIG. 53 shows a clamping assembly with a flat preform; and

FIG. 54 shows a microlens array comprising a round carrier.

DETAILED DESCRIPTION

The disclosure relates to a method for producing an optical element orheadlight lens according to the claims, wherein it is provided, interalia, that a blank made of non-borosilicate glass and/or soda-lime glass(soda lime silica glass) is heated and/or provided and, after beingheated and/or provided, is press-molded, for example on both sides,between a first mold, for example for molding and/or press-molding afirst optically active surface of the optical element, and at least onesecond mold, for example for molding and/or press-molding a secondoptically active surface of the optical element, to form the opticalelement, wherein the first optically active surface and/or the secondoptically active surface is sprayed with a surface-treatment agent(after the press-molding), wherein the surface-treatment agent comprisesa solvent and a solid dissolved in the solvent, and wherein it is forexample provided that the solvent or the solvent comprising the soliddissolved therein is thoroughly mixed with a gas and/or is dispersed bymeans of the gas.

Within the meaning of this disclosure, a solvent may optionally also bea solvent mixture. Within the meaning of this disclosure, a solvent or asolid dissolved in the solvent may optionally also be a solid mixture.Within the meaning of this disclosure, a gas may optionally also be agas mixture.

By contrast with the treatment of hollow glass and flat glass disclosedin DE 10 2006 034 431 A1 and EP 2 043 962 B1, the present disclosurerelates to the treatment of optically active surfaces. In this case,particularly high requirements are placed on the cooling, since not onlymechanical damage, such as cracks, could result in the object becomingunusable, but also internal strain, due to excessively rapid cooling.Therefore, it is all the more surprising that hot optically activesurfaces can be successfully treated in a suitable manner by misting ornebulizing a spray mist or by using a spray mist, in order to increaseits hydrolytic resistance.

Within the meaning of this disclosure, soda-lime glass for examplecomprises

60 to 75 wt. % SiO₂ and

3 to 12 wt. % CaO,

or

70 to 75 wt. % SiO₂ and

3 to 12 wt. % CaO.

Within the meaning of this disclosure, soda-lime glass for examplecomprises

60 to 75 wt. % SiO₂,

3 to 12 wt. % K₂O and

3 to 12 wt. % CaO,

or

70 to 75 wt. % SiO₂,

3 to 12 wt. % K₂O and

3 to 12 wt. % CaO.

Within the meaning of this disclosure, soda-lime glass for examplecomprises

60 to 75 wt. % SiO₂,

3 to 12 wt. % Na₂O,

3 to 12 wt. % K₂O and

3 to 12 wt. % CaO,

or

70 to 75 wt. % SiO₂,

3 to 12 wt. % Na₂O,

3 to 12 wt. % K₂O and

3 to 12 wt. % CaO.

Within the meaning of this disclosure, soda-lime glass for examplecomprises

0.2 to 2 wt. % Al₂O₃,

60 to 75 wt. % SiO₂,

3 to 12 wt. % Na₂O,

3 to 12 wt. % K₂O and

3 to 12 wt. % CaO,

Within the meaning of this disclosure, soda-lime glass for examplecomprises

0.2 to 2 wt. % Al₂O₃,

0.1 to 1 wt. % Li₂O,

60 to 75 wt. % SiO₂,

3 to 12 wt. % Na₂O,

3 to 12 wt. % K₂O and

3 to 12 wt. % CaO,

or

0.2 to 2 wt. % Al₂O₃,

0.1 to 1 wt. % Li₂O,

70 to 75 wt. % SiO₂,

3 to 12 wt. % Na₂O,

3 to 12 wt. % K₂O and

3 to 12 wt. % CaO,

Within the meaning of this disclosure, soda-lime glass for examplecomprises

0.2 to 2 wt. % Al₂O₃,

0.1 to 1 wt. % Li₂O,

0.3, for example 0.4, to 1.5 wt. % Sb₂O₃,

60 to 75 wt. % SiO₂,

3 to 12 wt. % Na₂O,

3 to 12 wt. % K₂O and

3 to 12 wt. % CaO,

such as DOCTAN®, or

0.2 to 2 wt. % Al₂O₃,

0.1 to 1 wt. % Li₂O,

0.3, for example 0.4, to 1.5 wt. % Sb₂O₃,

70 to 75 wt. % SiO₂,

3 to 12 wt. % Na₂O,

3 to 12 wt. % K₂O and

3 to 12 wt. % CaO.

In one configuration, it is provided that the solid comprises aluminum,aluminum chloride, aqueous aluminum chloride, aluminum salt, fatty-acidaluminum salts, phosphate, potassium phosphate, sodium phosphate, KO2,KOH, KNO3, silicate, SiO2, potassium silicate and/or potassium, orconsists of one or more of these constituents.

In another exemplary configuration, it is provided that the solventcomprises water, suspension agents, alcohol, methanol, ethanol,carbon-based solvents and/or isopropanol or consists of one or more ofthese constituents.

In another exemplary configuration, it is provided that the gascomprises air, nitrogen, hydrogen, carbon dioxide, HF, HCl and/or SO2 orconsists of one or more of these constituents.

In another exemplary configuration, it is provided that the firstoptically active surface is exposed to a different surface-treatmentagent from the second optically active surface.

In this case, it is for example provided that the optically activesurface provided as a light entry surface is exposed to asurface-treatment agent of which the proportion of silicate, potassiumsilicate and/or KOH is greater than that of the surface-treatment agentto which the optically active surface provided as a light exit surfaceis exposed.

It may be provided that at least one optically active surface isfire-polished before the treatment with surface-treatment agent. In oneconfiguration, it is for example provided that only the underside isfire-polished. This is, for example, provided in connection with aconfiguration of the lower optically active surface as a planar surface.It has been found to be suitable, when fire polishing is provided, for awaiting time to be allowed to elapse before the surface is exposed tothe surface-treatment agent. The waiting time is for example at leasttwo seconds, for example at least three seconds, for example at leastfour seconds. In one configuration, the fire polishing lasts no longerthan three seconds, for example no longer than two seconds. For largelenses, waiting times or hold times may for example be at least 20seconds but, for example, no more than 50 seconds.

Within the meaning of this disclosure, the surface-treatment agent forexample comprises aluminum, aluminum powder having a particle size of100 μm, aluminum powder having a particle size of ≤85 μm, aluminumpowder having a particle size of ≤65 μm (cf. also DE 10 2012 019 985B4).

According to one embodiment, the surface-treatment agent comprises,based on the total mass of the surface-treatment agent, 25 to 65 wt. %(for example 35 to 55 wt. %) water, 30 to 70 wt. % (for example 40 to 60wt. %) potassium phosphate, 1 to 8 wt. % (for example 2 to 6 wt. %)sodium phosphate and 0.001 to 0.010 wt. % (for example 0.002 to 0.006wt. %) aluminum, wherein the constituents do not add up to more than100%. In another embodiment, the surface-treatment agent comprises,based on the total mass of the surface-treatment agent, 35 to 65 wt. %or 25 to 55 wt. % water. According to another embodiment, thesurface-treatment agent comprises 40 to 70 wt. % or 30 to 60 wt. %potassium phosphate. In another embodiment, the surface-treatment agentcomprises 2 to 8 wt. % or 1 to 6 wt. % sodium phosphate. According toanother embodiment, the surface-treatment agent comprises 0.002 to 0.010wt. % or 0.001 to 0.006 wt. % aluminum.

In an exemplary configuration, the first optically active surface andthe second optically active surface are sprayed with thesurface-treatment agent at least partially simultaneously (overlappingin time).

In another exemplary configuration, the temperature of the opticalelement and/or the temperature of the first optically active surfaceand/or the temperature of the second optically active surface duringspraying with surface-treatment agent is no less than TG or TG+20 K,wherein TG denotes the glass transition temperature. In anotherconfiguration, the temperature is no less than TG-50 K.

In another exemplary configuration, the temperature of the opticalelement and/or the temperature of the first optically active surfaceand/or the temperature of the second optically active surface duringspraying with surface-treatment agent is no greater than TG+150 K, forexample no greater than TG+100 K. By contrast with the high temperaturesdescribed in EP 2 043 962 B1, the yield could be improved at lowertemperatures below TG+100 K (but above TG), and therefore thistemperature range is particularly suitable for the surface treatment inthe above-mentioned sense as part of industrial manufacturing.

In another exemplary configuration, the surface-treatment agent in theform of a spray agent is sprayed onto the optically active surface,wherein the surface-treatment agent forms droplets, of which the sizeand/or the average size and/or the diameter and/or the average diameteris no greater than 50 μm.

In another exemplary configuration, the surface-treatment agent in theform of a spray agent is sprayed onto the optically active surface,wherein the surface-treatment agent forms droplets, of which the sizeand/or the average size and/or the diameter and/or the average diameteris no less than 10 μm.

In another exemplary configuration, the surface-treatment agent issprayed so as to be mixed with compressed air. In another exemplaryconfiguration, compressed air, for example in combination with a mixingnozzle or dual-substance nozzle, is used for generating a spray mist forthe surface-treatment agent. In another exemplary configuration, thesurface-treatment agent is sprayed so as to be mixed with gas. In anexemplary configuration, a gas or gas mixture (for example incombination with a pressure of at least two bar), for example incombination with a mixing nozzle or dual-substance nozzle, is used forgenerating a spray mist for the surface-treatment agent. The gas ismixed with the surface-treatment agent under pressure (e.g. at least twobar or at least three bar), for example. The gas is, for example, mixedwith the gas (immediately) before impinging on the optically activesurface. In one configuration, the gas may be or contain nitrogen and/orcarbon dioxide.

In another exemplary configuration, the optically active surface issprayed with the surface-treatment agent before the optical element iscooled in a cooling path for cooling in accordance with a coolingregime.

It is for example provided that residues are removed, for example washedaway, from the surface-treatment process. This may for example becarried out using water, without the addition of cleaning agents. Afterbeing treated with the surface-treatment agent, the optical elements mayhave a (white) deposit, for example the reaction product. DI water mayfor example be used for cleaning the optical elements. DI water isdemineralized water. The abbreviation DI stands for “deionized”. Thecleaning may for example be carried out at a water temperature of 60° C.of the DI water. It is not necessary to use a washing agent such asCEROWEG, which is known from WO 2019 243 343 A1.

It is for example provided that the optical element or lens has atransmission of greater than 90% after washing and/or removing residuesfrom the surface-treatment process.

In another exemplary configuration, an optically active surface issprayed with the surface-treatment agent for no longer than 4 seconds.Here, an optically active surface is sprayed with the surface-treatmentagent for example for no longer than 3 seconds, for example for nolonger than 2 seconds, for example for no longer than one second. Inthis process, the optically active surface is sprayed until it has beensprayed with no less than 0.05 ml surface-treatment agent and/or with nomore than 0.5 ml, for example 0.2 ml, surface-treatment agent.

It is for example provided that, after being sprayed withsurface-treatment agent, the headlight lens consists of at least 90%,for example at least 95%, for example (substantially) 100%, quartz glasson the surface. It is for example provided that the following isapplicable in relation to the oxygen bonding to silicon on the surfaceof the headlight lens or the optical element

$\frac{Q(4)}{{Q(4)} + {Q(3)}} \geq 0.9$for example

$\frac{Q(4)}{{Q(4)} + {Q(3)}} \geq {{0.9}5}$

In the above, Q(3) and Q(4) denote the crosslinking of the oxygen ionswith the silicon ion, wherein 3 oxygen ions (Q(3)) or 4 oxygen ions(Q(4)) are arranged at the tetrahedron corners of the silicon ion. Theproportion of quartz glass decreases towards the interior of theheadlight lens or optical element, wherein, at a depth (distance fromthe surface) of 5 μm, it is for example provided that the proportion ofquartz glass is at least 10%, for example at least 5%. It is for exampleprovided that the following is applicable in relation to the oxygenbonding to silicon of the headlight lens or the optical element at adepth of 5 μm

${\frac{Q(4)}{{Q(4)} + {Q(3)}} \geq 0}{.1}$for example

${\frac{Q(4)}{{Q(4)} + {Q(3)}} \geq 0}{.05}$

It is for example provided that the proportion of quartz glass at adepth (distance from the surface) of 5 μm is no greater than 50%, forexample no greater than 25%. It is for example provided that thefollowing is applicable in relation to the oxygen bonding to silicon ofthe headlight lens or the optical element at a depth of 5 μm

$\frac{Q(4)}{{Q(4)} + {Q(3)}} \geq {0.5}$for example

${\frac{Q(4)}{{Q(4)} + {Q(3)}} \geq 0}{.25}$

It may be provided that the concentration of sodium ions in the interiorof the lens is (additionally) higher than in the region close to thesurface. Within the meaning of this disclosure, “close to the surface”may mean a depth of no greater than 5 μm, for example. It may beprovided that the concentration of aluminum ions in the interior of thelens is (additionally) lower than in the region close to the surface. Itmay be provided that, during the treatment with surface-treatment agent,ion exchange takes place to some extent between ions in the glass or itsregion close to the surface and the surface-treatment agent.

In another exemplary configuration, the first mold is moved by means ofan actuator for moving the first mold by the first mold and the actuatorbeing connected by means of a first movable guide rod and at least onesecond movable guide rod, for example at least one third movable guiderod, wherein the first movable guide rod is guided in a recess in afixed guide element and the second movable guide rod is guided in arecess in the fixed guide element and the optional third movable guiderod is guided in a recess in the fixed guide element, wherein it is forexample provided that the deviation in the position of the moldorthogonally to the movement direction of the mold from the targetposition of the mold orthogonally to the movement direction of the moldis no greater than 20 μm, for example no greater than 15 μm, for exampleno greater than 10 μm.

In another exemplary configuration, the at least one second mold ismoved by means of an actuator for moving the second mold in a frame,which comprises a first fixed guide rod, at least one second fixed guiderod and for example at least one third guide rod, wherein the firstfixed guide rod, the at least one second fixed guide rod and theoptional at least one third guide rod are connected at one end by anactuator-side fixed connector and at the other end by a mold-side fixedconnector, wherein the at least one second mold is fixed to a movableguide element, which comprises a recess through which the first fixedguide rod is guided, another recess through which the at least onesecond fixed guide rod is guided, and optionally another recess throughwhich the optional third fixed guide rod is guided, wherein it is forexample provided that the deviation in the position of the moldorthogonally to the movement direction of the mold from the targetposition of the mold orthogonally to the movement direction of the moldis no greater than 20 μm, for example no greater than 15 μm, for exampleno greater than 10 μm.

In an exemplary configuration, it is for example provided that the firstmold is moved by means of an actuator for moving the first mold by thefirst mold and the actuator for moving the first mold being connected bymeans of a first movable guide rod and at least one second movable guiderod, for example at least one third movable guide rod, wherein the firstmovable guide rod is guided in a recess in a fixed guide element and thesecond movable guide rod is guided in a recess in the fixed guideelement and the optional third movable guide rod is guided in a recessin the fixed guide element.

In another exemplary configuration, it is provided that the fixed guideelement is identical to the mold-side fixed connector or is indirectlyor directly fixed thereto.

In another exemplary configuration, the first mold is a lower moldand/or the second mold is an upper mold.

In an exemplary configuration, it is provided that, before pressing, theblank is placed onto an annular or free-form support surface of acarrier body having a hollow cross section, and is heated on the carrierbody, for example such that a temperature gradient is produced in theblank such that the blank is cooler in its interior than on its outerregion. It is for example provided that the support surface is cooled bymeans of a coolant flowing through the carrier body, wherein it is forexample provided that the support surface spans a base surface that isnot circular. In this case, a geometry of the support surface or ageometry of the base surface of the support surface is for exampleprovided which corresponds to the geometry of the blank (to be heated),wherein the geometry is selected such that the blank rests on the outerregion of its underside (underside base surface). The diameter of theunderside or the underside base surface of the blank is at least 1 mmgreater than the diameter of the base surface spanned (by the carrierbody or its support surface). In this sense, it is for example providedthat the geometry of the surface of the blank facing the carrier bodycorresponds to the support surface or the base surface. This for examplemeans that, after the forming process or the pressing or press-molding,the part of the blank resting on the carrier body or contacting thecarrier body during heating is arranged in an edge region of theheadlight lens which lies outside the optical path and rests on atransport element (see below) or its (corresponding) support surface,for example.

An annular support surface may comprise small discontinuities. Withinthe meaning of this disclosure, a base surface is for example animaginary surface (in the region of which the blank resting on thecarrier body is not in contact with the carrier body), which lies in theplane of the support surface and is surrounded by this support surface,plus the support surface. It is for example provided that the blank andthe carrier body are coordinated with one another. This is for exampleunderstood to mean that the edge region of the blank rests on thecarrier body on its underside. An edge region of a blank can beunderstood to mean the outer 10% or the outer 5% of the blank or itsunderside, for example.

Within the meaning of this disclosure, a blank is for example aportioned glass part or a preform or a gob.

Within the meaning of this disclosure, an optical element is for examplea lens, for example a headlight lens or a lens-like free-form. Withinthe meaning of this disclosure, an optical element is for example a lensor a lens-like free-form comprising a supporting edge that iscircumferential, discontinuous or circumferential in a discontinuousmanner. Within the meaning of this disclosure, an optical element maye.g. be an optical element as described in WO 2017/059945 A1, WO2014/114309 A1, WO 2014/114308 A1, WO 2014/114307 A1, WO 2014/072003 A1,WO 2013/178311 A1, WO 2013/170923 A1, WO 2013/159847 A1, WO 2013/123954A1, WO 2013/135259 A1, WO 2013/068063 A1, WO 2013/068053 A1, WO2012/130352 A1, WO 2012/072187 A2, WO 2012/072188 A1, WO 2012/072189 A2,WO 2012/072190 A2, WO 2012/072191 A2, WO 2012/072192 A1, WO 2012/072193A2, or PCT/EP2017/000444, for example. Each of these documents isincorporated by reference in its entirety. The claimed method isapplicable to non-symmetrical headlight lenses and non-rotationallysymmetrical headlight lenses, for example. The claimed method isapplicable to headlight lenses having non-symmetrical contours and tonon-rotationally symmetrical contours, for example. The claimed methodis applicable for example to headlight lenses having deterministicsurface structures, as disclosed in WO 2015/031925 A1, for example, andfor example having deterministic, non-periodic surface structures, asdisclosed in DE 10 2011 114 636 A1, for example.

In an exemplary configuration, the base surface is polygon-shaped orpolygonal, but for example with rounded corners, wherein it is forexample provided that the underside base surface of the blank is alsopolygon-shaped or polygonal, but for example with rounded corners. Inanother exemplary configuration, the base surface is triangle-shaped ortriangular, but for example with rounded corners, wherein it is forexample provided that the underside base surface of the blank is alsotriangle-shaped or triangular, but for example with rounded corners. Inone configuration, the base surface is rectangle-shaped or rectangular,but for example with rounded corners, wherein it is for example providedthat the underside base surface of the blank is also rectangle-shaped orrectangular, but for example with rounded corners. In another exemplaryconfiguration, the base surface is square, but for example with roundedcorners, wherein it is for example provided that the underside basesurface of the blank is also square, but for example with roundedcorners. In another exemplary configuration, the base surface is oval,wherein it is for example provided that the underside base surface ofthe blank is also oval.

In another exemplary configuration, the carrier body is tubular at leastin the region of the support surface. The carrier body for exampleconsists (at least substantially) of steel or high-alloy steel (i.e. forexample a steel in which the average mass content of at least one alloyelement is 5%) or of a tube made of steel or high-alloy steel. Inanother exemplary configuration, the diameter of the hollow crosssection of the carrier body or the internal tube diameter, at least inthe region of the support surface, is no less than 0.5 mm and/or nogreater than 1 mm. In another exemplary configuration, the externaldiameter of the carrier body or the external tube diameter, at least inthe region of the support surface, is no less than 2 mm and/or nogreater than 4 mm, for example no greater than 3 mm. In anotherexemplary configuration, the radius of curvature of the support surfaceorthogonally to the flow direction of the coolant is no less than 1 mmand/or no greater than 2 mm, for example no greater than 1.5 mm. Inanother exemplary configuration, the ratio of the diameter of the hollowcross section of the carrier body, at least in the region of the supportsurface, to the external diameter of the carrier body, at least in theregion of the support surface, is no less than ¼ and/or no greater than½. In another exemplary configuration, the carrier body is uncoated atleast in the region of the support surface. In another exemplaryconfiguration, coolant flows through the carrier body in accordance withthe counterflow principle. In another exemplary configuration, thecoolant is additionally and/or actively heated. In another exemplaryconfiguration, the carrier body comprises at least two flow channels forthe coolant flowing therethrough, which each only extend over a sectionof the annular support surface, wherein it is for example provided thattwo flow channels are connected in a region in which they leave thesupport surface by means of metal filler material, for example solder.

In another exemplary configuration, it is provided that, afterpress-molding, the optical element is placed on a transport element, issprayed with surface-treatment agent on the transport element and,thereafter or subsequently, passes through an annealing kiln on thetransport element without an optical surface of the optical elementbeing contacted. Within the meaning of this disclosure, an annealingkiln is for example used for the controlled cooling of the opticalelement (for example with the addition of heat). Exemplary coolingregimes may e.g. be found in “Werkstoffkunde Glas” [Glass MaterialsScience], 1^(st) edition, VEB Deutscher Verlag für Grundstoffindustrie,Leipzig VLN 152-915/55/75, LSV 3014, editorial deadline: 1.9.1974, ordernumber: 54107, e.g. page 130 and “Glastechnik—BG 1/1—Werkstoff Glas”[Glass Technology—vol. 1/1—Glass: The Material], VEB Deutscher Verlagfür Grundstoffindustrie, Leipzig 1972, e.g. page 61 ff (incorporated byreference in its entirety). It is necessary to comply with a coolingregime of this kind in order to prevent any internal stresses within theoptical element or the headlight lens, which, although they are notvisible upon visual inspection, can sometimes significantly impair thelighting properties as an optical element of a headlight lens. Theseimpairments result in a corresponding optical element or headlight lensbecoming unusable. It has surprisingly been found that, althoughspraying the hot optical element or headlight lens after press-moldingor after removal from the mold following the press-molding changes thecooling regime, the resulting optical stresses are negligible. It isalso surprising that a corresponding headlight lens ranges between theabove-mentioned optical tolerances in relation to its optical property,although the refractive index is reduced by the proportion of quartzglass on the surface.

In an exemplary configuration, the transport element consists of steel.For clarification: The transport element is not part of the lens (orheadlight lens), and the lens (or headlight lens) and the transportelement are not part of a common, integral body.

In another exemplary configuration, the transport element is heated, forexample inductively, before receiving the optical element. In anotherexemplary configuration, the transport element is heated at a heatingrate of at least 20 K/s, for example of at least 30 K/s. In anotherexemplary configuration, the transport element is heated at a heatingrate of no greater than 50 K/s. In another exemplary configuration, thetransport element is heated by means of an energized winding/coilwinding which is arranged above the transport element.

In another exemplary configuration, the optical element comprises asupport surface, which lies outside the light path provided for theoptical element, wherein the support surface, for example only thesupport surface, is in contact with a corresponding support surface ofthe transport element when the optical element is placed on thetransport element. In another exemplary configuration, the supportsurface of the optical element is on the edge of the optical element. Inanother exemplary configuration, the transport element comprises atleast one limiting surface for orienting the optical element on thetransport element and for limiting or preventing a movement of theoptical element on the transport element. In one configuration, thelimiting surface or surfaces are provided above the correspondingsupport surface of the transport element. In another configuration, (atleast) two limiting surfaces are provided, wherein it may be providedthat one limiting surface is below the corresponding support surface ofthe transport element and one limiting surface is above thecorresponding support surface of the transport element. In anotherexemplary configuration, the transport element is adapted, i.e.manufactured, for example milled, to the optical element or the supportsurface of the optical element.

The transport element or the support surface of the transport element isannular, for example, but is not circular, for example.

In another exemplary configuration, the preform is produced, cast and/ormolded from molten glass. In another exemplary configuration, the massof the preform is 20 g to 400 g.

In another exemplary configuration, the temperature gradient of thepreform is set such that the temperature of the core of the preform isabove 10 K+T_(G).

In another exemplary configuration, to reverse its temperature gradient,the preform is first cooled, for example with the addition of heat, andthen heated, wherein it is for example provided that the preform isheated such that the temperature of the surface of the preform afterheating is at least 100° K, for example at least 150° K, higher than theglass transition temperature T_(G). The glass transition temperatureT_(G) is the temperature at which the glass becomes hard. Within themeaning of this disclosure, the glass transition temperature T_(G) isfor example intended to be the temperature of the glass at which it hasa viscosity log in a range around 13.2 dPas (corresponding to 10^(13.2)Pas), for example between 13 (corresponding to 10¹³ Pas) and 14.5 dPas(corresponding to 10^(14.5) Pas). In relation to the glass type B270,the transition temperature T_(G) is approximately 530° C.

In another exemplary configuration, the temperature gradient of thepreform is set such that the temperature of the upper surface of thepreform is at least 30 K, for example at least 50 K, above thetemperature of the lower surface of the preform. In another exemplaryconfiguration, the temperature gradient of the preform is set such thatthe temperature of the core of the preform is at least 50 K below thetemperature of the surface of the preform. In another exemplaryconfiguration, the preform is cooled such that temperature of thepreform before the heating is T_(G)−80 K to T_(G)+30 K. In anotherexemplary configuration, the temperature gradient of the preform is setsuch that the temperature of the core of the preform is 450° C. to 550°C. The temperature gradient is for example set such that the temperaturein the core of the preform is below T_(G) or close to T_(G). In anotherexemplary configuration, the temperature gradient of the preform is setsuch that the temperature of the surface of the preform is 700° C. to900° C., for example 750° C. to 850° C. In another exemplaryconfiguration, the preform is heated such that its surface assumes atemperature (for example immediately before pressing) that correspondsto the temperature at which the glass of the preform has a viscosity logbetween 5 (corresponding to 10⁵ Pas) and 8 dPas (corresponding to 10⁸Pas), for example a viscosity log between 5.5 (corresponding to 10^(5.5)Pas) and 7 dPas (corresponding to 10⁷ Pas).

It is for example provided that, before reversing the temperaturegradient, the preform is removed from a mold for molding or producingthe preform. It is for example provided that the temperature gradient isreversed outside a mold. Within the meaning of this disclosure, coolingwith the addition of heat for example means that cooling is carried outa temperature of greater than 100° C.

Within the meaning of this disclosure, press-molding is for exampleunderstood to mean pressing a (for example optically active) surfacesuch that subsequent finishing of the contour of this (for exampleoptically active) surface is or can be omitted or is not provided. It isthus for example provided that a press-molded surface is not polishedafter the press-molding. Polishing, which influences the surface finishbut not the contours of the surface, may be provided in some cases.Press-molding on both sides can for example be understood to mean that a(for example optically active) light exit surface is press-molded and a(for example optically active) light entry surface that is for exampleopposite the (for example optically active) light exit surface islikewise press-molded.

In one configuration, the blank is placed onto an annular supportsurface of a carrier body having a hollow cross section, and is heatedon the carrier body for example such that a temperature gradient is setin the blank such that the blank is cooler in its interior than on itsouter region, wherein the support surface is cooled by means of acoolant flowing through the carrier body, wherein the blank made ofglass, after being heated, is press-molded, for example on both sides,to form the optical element, wherein the carrier body comprises at leasttwo flow channels for the coolant flowing therethrough, which each onlyextend over a section of the annular support surface, and wherein twoflow channels are connected in a region in which they leave the supportsurface by means of metal filler material, for example solder.

Within the meaning of this disclosure, a guide rod may be a rod, a tube,a profile, or the like.

Within the meaning of this disclosure, “fixed” for example meansdirectly or indirectly fixed to a base of the pressing station or thepress or a base on which the pressing station or press stands. Withinthe meaning of this disclosure, two elements are then fixed to oneanother, for example, when it is not provided that they are movedrelative to one another for pressing.

For pressing, the first and the second mold are for example movedtowards one another such that they form a closed mold or cavity or asubstantially closed mold or cavity. Within the meaning of thisdisclosure, “moved towards one another” for example means that bothmolds are moved. It may, however, also mean that only one of the twomolds is moved.

Within the meaning of the disclosure, a recess for example includes abearing that couples or connects the recess to the corresponding guiderod. Within the meaning of this disclosure, a recess may be widened toform a sleeve or may be designed as a sleeve. Within the meaning of thisdisclosure, a recess may be widened to form a sleeve comprising an innerbearing or may be designed as a sleeve comprising an inner bearing.

In a matrix headlight, the optical element or a corresponding headlightlens is for example used as a secondary lens for imaging front optics.Within the meaning of this disclosure, front optics are for examplearranged between the secondary optics and a light-source assembly.Within the meaning of this disclosure, front optics are for examplearranged in the light path between the secondary optics and thelight-source assembly. Within the meaning of this disclosure, frontoptics are for example an optical component for forming a lightdistribution depending on the light that is generated by thelight-source assembly and is directed therefrom into the front optics.Here, a light distribution is generated or formed for example by TIR,i.e. by total reflection.

The optical element or a corresponding lens is also used in a projectionheadlight, for example. In the configuration as a headlight lens for aprojection headlight, the optical element or a corresponding lens formsthe edge of a light stop in the form of a cut-off line on thecarriageway.

Within the meaning of this disclosure, a motor vehicle is for example aland vehicle that can be used individually in road traffic. Within themeaning of this disclosure, motor vehicles are not limited to landvehicles comprising internal combustion engines, for example.

Advantages and details will become clear from the following descriptionof embodiments. In the drawings:

FIG. 1 and FIGS. 1A and 1B show a schematically shown device 1 or 1A and1B for carrying out a method shown in FIG. 2A or 2B for producingoptical elements, such as optical lenses, for example motor-vehicleheadlight lenses, such as the (motor-vehicle) headlight lens 202 shownschematically in FIG. 34 , or (lens-like) free-forms, for example formotor-vehicle headlights, for example the use thereof as described inthe following with reference to FIG. 45 .

FIG. 34 is a schematic view of a motor-vehicle headlight 201 (projectionheadlight) of a motor vehicle 20, comprising a light source 210 forgenerating light, a reflector 212 for reflecting light that can begenerated by means of the light source 210, and a light stop 214. Themotor-vehicle headlight 201 also comprises a headlight lens 202 forimaging an edge 215 of the light stop 214 as a cut-off line 220 by meansof light that can be generated by the light source 210. Typicalrequirements placed on the cut-off line or on the light distributiontaking into account or incorporating the cut-off line are disclosed e.g.in Bosch—Automotive Handbook, 9^(th) edition, ISBN 978-1-119-03294-6,page 1040. Within the meaning of this disclosure, a headlight lens ise.g. a headlight lens by means of which a cut-off line can be generated,and/or a headlight lens by means of which the requirements according toBosch—Automotive Handbook, 9th edition, ISBN 978-1-119-03294-6(incorporated by reference in its entirety), page 1040, can be met. Theheadlight lens 202 comprises a lens body 203 made of glass, which has asubstantially planar (for example optically active) surface 205 facingthe light source 210 and a substantially convex (for example opticallyactive) surface 204 facing away from the light source 210. The headlightlens 202 also comprises a (for example circumferential) edge 206, bymeans of which the headlight lens 202 can be fastened in themotor-vehicle headlight 201. The elements in FIG. 34 are not necessarilyshown to scale for the sake of simplicity and clarity. Therefore, forexample, the scales of some elements are exaggerated compared with otherelements in order to improve the understanding of the embodiment of thepresent disclosure.

FIG. 35 is a view of the headlight lens 202 from below. FIG. 36 is across section through an embodiment of the headlight lens. FIG. 37 showsa detail of the headlight lens 202 marked by a dashed circle in FIG. 36. The planar (for example optically active) surface 205 projects in theform of a step 260 towards the optical axis 230 of the headlight lens202 beyond the lens edge 206 or beyond the surface 261 of the lens edge206 facing the light source 210, wherein the height h of the step 260 ise.g. no greater than 1 mm, for example no greater than 0.5 mm. Thenominal value of the height h of the step 260 is for example 0.2 mm.

The thickness r of the lens edge 206 according to FIG. 36 is at least 2mm, but no greater than 5 mm. According to FIGS. 35 and 36 , thediameter DL of the headlight lens 202 is at least 40 mm, but no greaterthan 100 mm. The diameter DB of the substantially planar (for exampleoptically active) surface 205 is equal to the diameter DA of the convexcurved optically active surface 204. In one configuration, the diameterDB of the substantially planar optically active surface 205 is nogreater than 110% of the diameter DA of the convex curved opticallyactive surface 204. In addition, the diameter DB of the substantiallyplanar optically active surface 205 is for example at least 90% of thediameter DA of the convex curved optically active surface 204. Thediameter DL of the headlight lens 202 is for example approximately 5 mmgreater than the diameter DB of the substantially planar opticallyactive surface 205 and/or than the diameter DA of the convex curvedoptically active surface 204. The diameter DLq of the headlight lens 202extending orthogonally to DL is at least 40 mm, but no greater than 80mm, and is less than the diameter DL. The diameter DLq of the headlightlens 202 is for example approximately 5 mm greater than the diameter DBqthat is orthogonal to DB.

In another exemplary configuration, the (optically active) surface 204intended to face away from the light source and/or the (opticallyactive) surface 205 intended to face the light source have a surfacestructure that scatters light (and is generated/pressed by molding). Asuitable light-scattering surface structure e.g. includes modulationand/or (surface) roughness of at least 0.05 μm, for example at least0.08 μm, and/or is configured as modulation optionally having anadditional (surface) roughness of at least 0.05 μm, for example of atleast 0.08 μm. Within the meaning of this disclosure, roughness isintended to be defined as Ra, for example in accordance with ISO 4287.In another exemplary configuration, the light-scattering surfacestructure may have a structure that simulates the surface of a golf ballor may be configured as a structure that simulates the surface of a golfball. Suitable light-scattering surface structures are disclosed in DE10 2005 009 556, DE 102 26 471 B4 and DE 299 14 114 U1, for example.Other configurations of light-scattering surface structures aredisclosed in the German patent specification 1 099 964, DE 36 02 262 C2,DE 40 31 352 A1, U.S. Pat. No. 6,130,777, US 2001/0033726 A1, JP10123307 A, JP 09159810 A, DE 11 2018 000 084.2 and JP 01147403 A.

FIG. 39 shows an adaptive headlight or vehicle headlight F20 for thesituation-dependent or traffic-dependent illumination of thesurroundings or carriageway in front of the motor vehicle 20 on thebasis of a surround sensor system F2 of the motor vehicle 20. For thispurpose, the vehicle headlight F20 shown schematically in FIG. 39comprises an illumination device F4, which is actuated by means of acontroller F3 of the vehicle headlight F20. Light L4 generated by theillumination device F4 is emitted by the vehicle headlight F20 in theform of an illumination pattern L5 by means of an objective lens F5,which may comprise one or more optical lens elements or headlightlenses. Examples of corresponding illumination patterns are shown inFIGS. 40 and 41 , and the websitesweb.archive.org/web/20150109234745/http://www.audi.de/content/de/brand/de/vorsprung_durch_technik/content/2013/08/Audi-A8-erstrahlt-in-neuem-Licht.html(retrieved on 5 Sep. 2019) andwww.all-electronics.de/matrix-led-und-laserlicht-bietet-viele-vorteile/(retrievedon 2 Sep. 2019). In the configuration according to FIG. 41 , theillumination pattern L5 comprises full-beam regions L51, dimmed regionsL52 and cornering light L53.

FIG. 42 shows an embodiment of the illumination device F4, wherein itcomprises a light-source assembly F41 having a plurality of individuallyadjustable regions or pixels. Therefore, up to 100 pixels, up to 1,000pixels or no less than 1,000 pixels may for example be provided, whichcan be individually actuated by means of the controller F3 to the effectthat they can be individually activated or deactivated, for example. Itmay be provided that the illumination device F4 also comprises frontoptics F42 for generating a light pattern (such as L4) on the light exitsurface F421 on the basis of the accordingly actuated regions or pixelsof the light-source assembly F41 or according to the light L41 directedinto the front optics F42.

Within the meaning of this disclosure, matrix headlights may also bematrix SSL HD headlights. Examples of headlights of this kind are foundat the linkswww.springerprofessional.de/fahrzeug-lichttechnik/fahrzeugsicherheit/hella-bringt-neues-ssl-hd-matrix-lichtsystem-auf-den-markt/17182758(retrieved on 28 May 2020), www.highlight-web.de/5874/hella-ssl-hd/(retrieved on 28 May 2020) andwww.hella.com/techworld/de/Lounge/Unser-Digital-Light-SSL-HD-Lichtsystem-ein-neuer-Meilenstein-der-automobilen-Lichttechnik-55548/(retrieved on 28 May 2020).

FIG. 43 is a side view of an integral front optics array V1. FIG. 44 isa rear plan view of the front optics array V1. The front optics array V1comprises a base part V20, on which lenses V2011, V2012, V2013, V2014and V2015 and front optics V11 having a light entry surface V111, frontoptics V12 having a light entry surface V121, front optics V13 having alight entry surface V131, front optics V14 having a light entry surfaceV141 and front optics V15 having a light entry surface V151 are molded.The side surfaces V115, V125, V135, V145, V155 of the front optics V11,V12, V13, V14, V15 are press-molded and are formed such that light whichenters the relevant light entry surface V111, V121, V131, V141 or V151by means of a light source is subjected to total reflection (TIR), suchthat this light exits the base part V20 or the surface V21 of the basepart V20 which forms the common light exit surface of the front opticsV11, V12, V13, V14 and V15. The rounding radii between the light entrysurfaces V111, V121, V131, V141 and V151 at the transition to the sidesurface V115, V125, V135, V145 and V155 are e.g. 0.16 to 0.2 mm.

FIG. 45 is a schematic view of a vehicle headlight V201 or motor-vehicleheadlight. The vehicle headlight V201 comprises a light-source assemblyVL, for example comprising LEDs, for directing light into the lightentry surface V111 of the front optics V11 or the light entry surfacesV112, V113, V114 and V115 (not shown in greater detail) of the frontoptics V12, V13, V14 and V15. In addition, the vehicle headlight V201comprises a secondary lens V2 for imaging the light exit surface V21 ofthe front optics array V1.

Another suitable field of application for lenses produced according tothe disclosure is for example disclosed in DE 10 2017 105 888 A1 or theheadlight described with reference to FIG. 46 . In this case, by way ofexample, FIG. 46 shows a light module (headlight) M20 which comprises alight-emission unit M4 having a plurality of punctiform light sourcesthat are arranged in a matrix-like manner and each emit light ML4 (witha Lambert's emission characteristic), and also comprises a concave lensM5 and projection optics M6. In the example according to FIG. 46 shownin DE 10 2017 105 888 A1, the projection optics M6 comprise two lenseswhich are arranged one behind the other in the beam path and have beenproduced according to a method corresponding to the above-mentionedmethod. The projection optics M6 image the light ML4 emitted by thelight-emission unit M4 and light ML5 that is further shaped afterpassing through the concave lens M5, in the form of a resulting lightdistribution ML6 of the light module M20, on a carriageway in front ofthe motor vehicle in which the light module or headlight is (has been)installed.

The light module M20 comprises a controller denoted by reference signM3, which actuates the light-emission unit M4 on the basis of the valuesfrom a sensor system or surround sensor system M2. The concave lens M5comprises a concave curved exit surface on the side facing away from thelight-emission unit M4. The exit surface of the concave lens M5 deflectslight ML4 directed into the concave lens M5 from the light-emission unitM4 at a large emission angle towards the edge of the concave lens bymeans of total reflection, such that said light is not transmittedthrough the projection optics M6. According to DE 10 2017 105 888 A1,light beams that are emitted from the light-emission unit M4 at a “largeemission angle” are referred to as those light beams which (withoutarranging the concave lens M5 in the beam path) would be imaged poorly,for example in a blurred manner, on the carriageway by means of theprojection optics M6 owing to optical aberrations and/or could result inscattered light, which reduces the contrast of the imaging on thecarriageway (see also DE 10 2017 105 888 A1). It may be provided thatthe projection optics M6 can only image light in focus at an openingangle limited to approximately +/−20°. Light beams having opening anglesof greater than +/−20°, for example greater than +/−30°, are thereforeprevented from impinging on the projection optics M6 by arranging theconcave lens M5 in the beam path.

The light-emission unit M4 may be designed differently. According to oneconfiguration, the individual punctiform light sources of thelight-emission unit M4 each comprise a semiconductor light source, forexample a light-emitting diode (LED). The LEDs may be actuatedindividually or in groups in a targeted manner in order to activate ordeactivate or dim the semiconductor light sources. The light module M20e.g. comprises more than 1,000 individually actuatable LEDs. Forexample, the light module M20 may be designed as what is known as a μAFS(micro-structured adaptive front-lighting system) light module.

According to an alternative option, the light-emission unit M4 comprisesa semiconductor light source and a DLP or micromirror array, whichcomprises a large number of micromirrors which can be actuated andtilted individually, wherein each of the micromirrors forms one of thepunctiform light sources of the light-emission unit M4. The micromirrorarray for example comprises at least 1 million micromirrors, which mayfor example be tilted at a frequency of up to 5,000 Hz.

Another example of a headlight system or light module (DLP system) isdisclosed by the linkwww.al-lighting.com/news/article/digital-light-millions-of-pixels-on-the-road/(retrievedon 13 Apr. 2020). FIG. 47 schematically shows a corresponding headlightmodule or vehicle headlight for generating an illumination patterndenoted by GL7A in FIG. 48 . The adaptive headlight G20 schematicallyshown in FIG. 47 for the situation-dependent or traffic-dependentillumination of the surroundings or carriageway in front of the motorvehicle 20 on the basis of a surround sensor system G2 of the motorvehicle 20. Light GL5 generated by the illumination device G5 is shapedby means of a system of micromirrors G6, as also shown in DE 10 2017 105888 A1, to form an illumination pattern GL6 which, by means ofprojection optics G7 for adaptive illumination, radiates suitable lightGL7 in front of the motor vehicle 20 or in the surroundings onto thecarriageway in front of the motor vehicle 20. A suitable system G6 ofmovable micromirrors is disclosed by the linkwww.al-lighting.com/news/article/digital-light-millions-of-pixels-on-the-road/(retrievedon 13 Apr. 2020).

A controller G4 is provided for actuating the system G6 comprisingmovable micromirrors. In addition, the headlight G20 comprises acontroller G3 both for synchronizing with the controller G4 and foractuating the illumination device G5 on the basis of the surround sensorsystem G2. Details of the controllers G3 and G4 can be found at the linkwww.al-lighting.com/news/article/digital-light-millions-of-pixels-on-the-road/(retrievedon 13 Apr. 2020). The illumination device G5 may for example comprise anLED assembly or a comparable light-source assembly, optics such as afield lens (which, for example, has likewise been produced according tothe above-described method) and a reflector.

The vehicle headlight G20 described with reference to FIG. 47 may forexample be used in connection with other headlight modules or headlightsin order to obtain a superimposed overall light profile or illuminationpattern. This is shown by way of example in FIG. 49 , wherein theoverall illumination pattern is compiled from the illumination patternsGL7A, GL7B and GL7C. In this process, it may for example be providedthat the illumination pattern GL7C is generated by means of theheadlight 20 and the illumination pattern GL7B is generated by means ofthe headlight V201.

Sensor systems for the above-mentioned headlights for example comprise acamera and analysis or pattern recognition for analyzing a signalprovided by the camera. A camera for example comprises an objective lensor a multiple-lens objective lens as well as an image sensor for imagingan image generated by the objective lens on the image sensor. In aparticularly suitable manner, an objective lens is used as disclosed inU.S. Pat. No. 8,212,689 B2 (incorporated by reference in its entirety)and shown by way of example in FIG. 50 . An objective lens of this kindis particularly suitable because it prevents or significantly reducesparasitic images, since an objective lens of this kind can for exampleprevent a parasitic image of a vehicle coming in the other directionwith its lights on being confused with a vehicle driving in front withits lights on. A suitable objective lens, for example for infrared lightand/or visible light, images an object in an image plane, wherein, inrelation to the imaging of an object, it is applicable to each pointwithin the image circle of the objective lens or to at least one pointwithin the image circle of the objective lens that Pdyn≥70 dB, forexample Pdyn≥80 dB, for example Pdyn≥90 dB, wherein Pdyn is equal to10·log(Pmax/Pmn), as shown in FIG. 51 , wherein Pmax is the maximumluminous power of a point in the image plane for imaging a point on theobject, and wherein Pmin is the luminous power of another point in theimage plane for imaging the point on the object, the luminous power ofwhich in relation to the imaging of the point on the object is greaterthan the luminous power of each other point in the image plane inrelation to the imaging of the point on the object or wherein Pmin isthe maximum luminous power of the parasitic-image signals from the pointon the object as imaged at another point. The lenses or some of thelenses of the objective lens shown in FIG. 50 can be produced accordingto the claimed or disclosed method, wherein it is for example providedthat the accordingly produced lenses comprise a circumferential orpartially circumferential edge, in a departure from the view in FIG. 50.

Another embodiment for the use of the method described in the followingis the production of microlens arrays, for example microlens arrays forprojection displays. A microlens array of this kind and its use in aprojection display are shown in FIG. 52 . Microlens arrays andprojection displays are described in WO 2019/072324, DE 10 2009 024 894,DE 10 2011 076 083 and DE 10 2020 107 072, for example. The microlensarray according to FIG. 52 is an integral, pressed glass part (pressedfrom a gob), which integrally combines the substrate or carrier P403 andthe projection lenses P411, P412, P413, P414, P415. In addition, theprojection lenses P411, P412, P413, P414, P415 having a concave contour,or a parabolic contour are arranged one after the other. Owing to thisarrangement, the optical axis P4140 of the projection lenses, such asthe projection lens P414, is tilted relative to the orthogonal P4440 ofthe object structure P444 (see below), for example. A metal mask P404 isarranged on a side of the carrier P403 facing away from the projectionlenses P411, P412, P413, P414, P415, wherein said mask comprisesrecesses, in which object structures P441, P442, P443, P444 and P445 arearranged. An illumination layer P405 is arranged over the objectstructures. It may also be provided that the illumination layer P405comprises a transparent electrode, a light-emitting layer and areflective back electrode. A light source as disclosed in U.S. Pat. No.8,998,435 B2 also comes into consideration as an alternativeillumination means.

The device 1 according to FIG. 1 for producing optical elements such asthe headlight lens 202 comprises a melting unit 2, such as a trough, inwhich soda-lime glass, in the present embodiment DOCTAN®, is melted in aprocess step 120 according to FIG. 2A. The melting unit 2 may e.g.comprise an adjustable outlet 2B. In a process step 121, liquid glass isbrought from the melting unit 2 into a preform device 3 for producing apreform, such as a gob, for example having a mass of from 10 g to 400 g,for example a mass of from 50 g to 250 g, or a preform that is close tothe final contours (a preform that is close to the final contours has acontour that is similar to the contour of the motor-vehicle headlightlens to be pressed or to the lens-like free-form for motor-vehicleheadlights). This may e.g. comprise molds in which a defined quantity ofglass is cast. The preform is produced in a process step 122 by means ofthe preform device 3.

The process step 122 is followed by a process step 123, in which thepreform is transferred to the cooling apparatus 5 by means of a transferstation 4 and is cooled by means of the cooling apparatus 5 at atemperature of between 300° C. and 500° C., for example of between 350°C. and 450° C. In the present embodiment, the preform is cooled for over10 minutes at a temperature of 400° C., such that its temperature in theinterior is approximately 500° C. or greater, for example 600° C. orgreater, for example T_(G) or greater.

In a subsequent process step 124, the preform is heated by means of theheating apparatus 6 at a temperature of no less than 700° C. and/or nogreater than 1600° C., for example of between 1,000° C. and 1250° C.,wherein it is for example provided that the preform is heated such thatthe temperature of the surface of the preform after the heating is atleast 100° C., for example at least 150° C., greater than T_(G) and isfor example 750° C. to 900° C., for example 780° C. to 850° C. Acombination of the cooling apparatus 5 with the heating apparatus 6 isan example of a temperature-control apparatus for setting thetemperature gradient.

In one configuration, this temperature-control apparatus and/or thecombination of the heating apparatuses 5 and 6 is designed as ahood-type annealing furnace 5000, as shown in FIG. 14 . FIG. 14 shows apreform to be heated in the form of a gob 4001 on a support device 400designed as a lance. Heating coils 5001 are provided for heating the gob4001. In order to protect these heating coils 5001 against a defectivegob bursting open, the interior of the hood-type annealing furnace 5000is lined with a protective cover 5002. FIG. 15 is a view of thehood-type annealing furnace 5000 according to FIG. 14 from below, FIG.16 is a cross section through the protective cover 5002 according toFIG. 14 , and FIG. 17 is a view into the interior of the protectivecover 5002 according to FIG. 14 . In the embodiment according to FIG. 14, this protective cover 5002 is configured to be cup-shaped. In thisconfiguration, the protective cover 5002 comprises a cylindrical region5112, which transitions into a covering region 5122 via a rounded region5132. The radius of curvature of the curved region 5132 is between 5 mmand 20 mm, for example. In the embodiment according to FIG. 16 , theradius of curvature of the curved region 5132 is approximately 10 mm.The protective cover 5002 is secured in the hood-type annealing furnace5000 and is fixed by a nut 4002. In another preferred configuration, abayonet catch is provided, by means of which a protective cover can bechanged more rapidly.

FIG. 19 is a cross section through an embodiment of another protectivecover 5202. FIG. 20 is a view into the interior of the protective cover5202 according to FIG. 19 . The protective cover 5202 is likewiseconfigured to be cup-shaped, but also comprises a conical region 5242 inaddition to a cylindrical region 5212. The conical region 5242transitions into a covering region 5222 via a curvature 5232. Theconical region 5242 defines a volume which is between 30% and 50% of thevolume of the cavity in the protective cover 5202.

FIG. 21 is a cross section through an embodiment of another protectivecover 5302, FIG. 22 is a view into the interior of the protective cover5302 according to FIG. 21 , and FIG. 23 is a perspective view of theprotective cover 5302. The protective cover 5302 is likewise configuredto be cup-shaped, but also comprises a conical region 5342 in additionto a cylindrical region 5312. The conical region 5342 transitions into acovering region 5322 via a curvature 5332. The conical region 5342defines a volume which is between 30% and 50% of the volume of thecavity in the protective cover 5302.

The protective covers 5002, 5202, 5302 for example have the purpose ofprotecting the heating coils 5001 positioned in the furnace againstglass bursting open. If a gob bursts open in the furnace without thisprotective cover, SOME of the glass or the majority of the glass clingsto the heating coils 5001 and thus significantly impairs the heatingprocess for the next gob or even destroys the heating coils 5001 andthus destroys the entire functional capability of the furnace. Theprotective covers 5002, 5202, 5302 are removed after a gob has burst andare replaced with other protective covers. The protective covers 5002,5202, 5302 are adapted to the size of the furnace.

The heating coils 5001 can consist of or comprise a plurality ofindependently actuatable heating coils 5001A and 5001B. Because saidcoils are independently actuatable, a particularly suitable, for examplehomogeneous, temperature (distribution) can be obtained inside thefurnace or inside the protective covers 5002, 5202, 5303. In addition totheir function of reducing the severity of a gob bursting open, theprotective covers 5002, 5202, 5303 contribute to this desiredtemperature distribution. The protective covers consist of or comprisesilicon carbide, for example.

As explained below with reference to FIGS. 5 and 6 , the process steps123 and 124 are coordinated with one another such that a reversal of thetemperature gradient is obtained. In this case, FIG. 5 shows anexemplary preform 130 before entering the cooling apparatus 5 and FIG.15 shows the preform 130 with a reversed temperature gradient afterleaving the heating apparatus 6. While the blank is hotter inside thanoutside before the process step 123 (with a continuous temperaturecurve), it is hotter outside than inside after the process step 124(with a continuous temperature curve). The wedges denoted by referencesigns 131 and 132 symbolize the temperature gradients here, wherein thewidth of a wedge 131 or 132 symbolizes a temperature.

In order to reverse its temperature gradient, in one configuration, apreform resting on a cooled lance (not shown) is moved through thetemperature-control device comprising the cooling apparatus 5 and theheating apparatus 6 (for example substantially continuously) or is heldin one of the cooling apparatuses 5 and/or one of the heatingapparatuses 6. A cooled lance is disclosed in DE 101 00 515 A1 and in DE101 16 139 A1. Depending on the shape of the preform, FIGS. 3 and 4 showsuitable lances, for example. For example, coolant flows through thelance in accordance with the counterflow principle. Alternatively oradditionally, it may be provided that the coolant is additionally and/oractively heated.

For the term “lance”, the term “support device” is also used in thefollowing. The support device 400 shown in FIG. 3 comprises a carrierbody 401 having a hollow cross section and an annular support surface402. The carrier body 401 is tubular at least in the region of thesupport surface 402 and is uncoated at least in the region of thesupport surface 402. The diameter of the hollow cross section of thecarrier body 401, at least in the region of the support surface 402, isno less than 0.5 mm and/or no greater than 1 mm. The external diameterof the carrier body 401, at least in the region of the support surface,is no less than 2 mm and/or no greater than 3 mm. The support surface402 spans a square base surface 403 having rounded corners. The carrierbody 401 comprises two flow channels 411 and 412 for the coolant flowingtherethrough, which each only extend over a section of the annularsupport surface 402, wherein the flow channels 411 and 412 are connectedin a region in which they leave the support surface 402 by means ofmetal filler material 421 and 422, for example solder.

The support device 500 shown in FIG. 4 comprises a carrier body 501having a hollow cross section and an annular support surface 502. Thecarrier body 501 is tubular at least in the region of the supportsurface 502 and is uncoated at least in the region of the supportsurface 502. The diameter of the hollow cross section of the carrierbody 501, at least in the region of the support surface 502, is no lessthan 0.5 mm and/or no greater than 1 mm. The external diameter of thecarrier body 501, at least in the region of the support surface, is noless than 2 mm and/or no greater than 3 mm. The support surface 502spans an oval base surface 503. The carrier body 501 comprises two flowchannels 511 and 512 for the coolant flowing therethrough, which eachonly extend over a section of the annular support surface 502, whereinthe flow channels 511 and 512 are connected in a region in which theyleave the support surface 502 by means of metal filler material 521 and522, for example solder.

It may be provided that, after passing through the cooling apparatus 5(in the form of an annealing kiln), preforms are removed and aresupplied by means of a transport apparatus 41, for example, to anintermediate storage unit (e.g. in which they are stored at roomtemperature). In addition, it may be provided that preforms areconducted to the transfer station 4 by means of a transport apparatus 42and are phased into the continuing process by heating in the heatingapparatus 6 (for example starting from room temperature).

In a departure from the method described with reference to FIG. 2A, inthe method described with reference to FIG. 2B, the process step 121 isfollowed by the process step 122′, in which the cast gob is transferredto an annealing kiln 49 of the device 1A, as shown in FIG. 1A, by meansof a transfer station 4. In this sense, an annealing kiln is for examplea conveying apparatus, such as a conveyor belt, through which a gob isguided and is cooled in the process, for example with the addition ofheat. The cooling is carried out to a certain temperature above roomtemperature or to room temperature, wherein the gob is cooled down toroom temperature in the annealing kiln 49 or outside the annealing kiln49. It is for example provided that a gob rests on a base made ofgraphite or a base comprising graphite in the annealing kiln 49.

In the subsequent process step 123′ according to FIG. 2B, the gobs aresupplied to a device 1B. The devices 1A and 1B may be in close proximityto one another, but may also be further away from one another. In thelatter case, a transfer station 4A transfers the gobs from the annealingkiln 49 to a transport container BOX. The gobs are transported in thetransport container BOX to the device 1B, in which a transfer station 4Bremoves the gobs from the transport container BOX and transfers them toa hood-type annealing furnace 5000. The gobs are heated in the hood-typeannealing furnace 5000 (process step 124′).

Flat gobs, wafers or wafer-like preforms can also be used to producemicrolens arrays. Wafers of this kind may be square, polygonal or round,for example having a thickness of from 1 mm to 10 mm and/or a diameterof 4 inches to 5 inches. In a departure from the previously describedmethod, these preforms are not heated on support devices, as shown inFIGS. 3 and 4 , but are clamped, as shown in FIG. 53 . In this case, thereference sign T1 denotes a flat preform or wafer and reference signs T2and T3 denote clamping devices for clamping the flat preform T1 orwafer. In this clamping assembly T5 comprising the clamping devices T2and T3, this flat preform is heated in a heating apparatus, such as thehood-type annealing furnace 5000. In this case, it may be provided thatthis preform T1 is not inserted into the heating apparatus from below,but instead from the side. Furthermore, it is for example provided thatthe clamped flat preform T1 rotates in the heating apparatus in order toprevent the flat preform T1 from bowing. In this process, the preform T1is heated in the heating apparatus, for example while rotating, untilthe heated preform T1 can be pressed. The preform T1 is then placed ontoa press mold (described in greater detail below) in a for examplerotating movement, wherein the clamping devices T 2 and T 3 of theclamping assembly T 4 are opened such that the preform T1 rests on thepress mold. During the pressing process, the clamping devices T 2 and T3 remain in the press. After the pressing process, the clamping devicesT 2 and T 3 grip the pressed preform T1 again and convey the preform T1into a region outside the press.

A press 8, onto which a preform is transferred by means of a transferstation 7, is provided behind the heating apparatuses 6 or 5000. Thepreform is press-molded, for example on both sides, to form an opticalelement, such as the headlight lens 202, in a process step 125 by meansof the press 8. A suitable mold set is disclosed e.g. in EP 2 104 651B1. FIG. 24 is a schematic view of a pressing station PS for pressing anoptical element from a heated blank. The pressing station PS is part ofthe press 8 according to FIGS. 1 and 1B. The pressing station PScomprises an upper pressing unit PO and a lower pressing unit PU. Forthe pressing, a mold OF (upper mold), which is moved by means of a pressdrive or by means of an actuator O10, and a mold UF (lower mold), whichis moved by means of a press drive or by means of an actuator U10, aremoved towards one another. The mold UF is connected to a mold-sidemovable connector U12, which is in turn connected to an actuator-sidemovable connector U11 by means of movable guide rods U51, U52. Theactuator U10 is in turn connected to the actuator-side movable connectorU11, such that the mold UF is movable by means of the actuator U10. Themovable guide rods U51 and U52 extend through recesses in a fixed guideelement UO such that any displacement or movement of the movable guiderods U51 and U52 and therefore of the mold UF perpendicularly to themovement direction is prevented or reduced or limited.

The pressing unit PO comprises an actuator O10, which moves the mold OFand is connected to a movable guide element O12. The pressing unit POalso comprises a frame, which is formed by an actuator-side fixedconnector O11 and a mold-side fixed connector O14 as well as fixed guiderods O51 and O52, which connect the actuator-side fixed connector O11 tothe mold-side fixed connector O14. The fixed guide rods O51 and O52 areguided through recesses in the movable guide element O12, such that theyprevent, reduce or avoid any movement or deflection of the mold OForthogonally to the movement direction of the actuator O10 or mold OF.

In the embodiment shown, the pressing units PO and PU are linked in thatthe fixed guide element UO is identical to the mold-side fixed connectorO14. By linking or chaining the two pressing units PO and PU of thepressing station PS together, particularly high quality (for example inthe form of contour accuracy) of the headlight lenses to be pressed isachieved.

The pressing station 800 comprises a lower pressing unit 801 and anupper pressing unit 802 (see FIG. 25 ), wherein FIG. 25 shows anembodiment of a pressing station 800, by means of which opticalelements, such as headlight lenses, can be pressed in a particularlypreferable and suitable manner. The pressing station 800 is anembodiment of the pressing station PS from FIG. 24 . The pressing unit801 is an embodiment of the lower pressing unit PU in FIG. 24 and thepressing unit 802 is an embodiment of the upper pressing unit PO in FIG.24 . The pressing station 800 comprises a pressing frame, which, in anexemplary configuration, comprises the interconnected rods 811 and 814as well as the interconnected rods 812 and 815. The rods 811 and 812 areinterconnected by a lower plate 817 and an upper connection part 816 andthus form a pressing frame, which receives the lower pressing unit 801and the upper pressing unit 802.

The lower pressing unit 801 comprises a press drive 840 corresponding tothe actuator U10, by means of which drive three rods 841, 842, 843 aremovable, in order to move a lower press mold 822 that is coupled to therods 841, 842, 843 and corresponds to the mold UF. The rods 841, 842,843 are guided through bores or holes (not shown) in the plate 817 and aplate 821, which prevent or considerably reduce a deviation or movementof the press mold 822 in a direction orthogonal to the movementdirection. The rods 841, 842, 843 are embodiments of the movable guiderods U51 and U52 according to FIG. 24 . The plate 817 is a configurationor implementation of the fixed guide element UO.

The upper pressing unit 802 shown in FIG. 26 comprises a press drive 850which corresponds to the actuator O10 and is held by the upperconnection part 816, which corresponds to the actuator-side fixedconnector O11. A plate 855 which corresponds to the movable guideelement O12 and comprises guide rods 851, 852 and 853 as well as anupper press mold 823 is guided by means of the press drive 850. Theguide rods 851, 852 and 853 correspond to the fixed guide rods OS1 andOS2 in FIG. 24 . The press mold 823 corresponds to the mold OF in FIG.24 . For the guidance, sleeves H851, H852 and H853 comprising bearingsL851 and L853 are also provided as an implementation of the recesses inthe movable guide plate O12 from FIG. 24 , which surround the guide rods851, 852 and 853. The plates 821 and 817 are fixed to one another andthus form the fixed guide element UO (plate 817) and the mold-side fixedconnector O14 (plate 821).

Reference sign 870 denotes a movement mechanism by means of which aninduction heater 879 comprising an induction loop 872 can be movedtowards the lower mold 822 in order to heat it by means of the inductionloop 872. After the heating by means of the induction loop 872, theinduction heater 879 is moved back into its starting position again. Agob or preform is placed onto the press mold 822 and, by moving thepress molds 822 and 823 towards one another, is press-molded (on bothsides) to form a headlight lens.

FIG. 27 shows another pressing station 800′, likewise as an embodimentof the pressing station PS according to FIG. 24 . In a modification tothe pressing station 800, a reinforcement profile P811, P812 is forexample provided for each of the rods 811, 812 or the rods 814, 815,wherein the reinforcement profile P811, P812 is connected to the rods811, 812, 814, 815 by means of clamps SP811, SP812, SP814, SP815. FIG.28 is, by way of example, a view of a detail of a clamp SP811 of thiskind, wherein one half of the clamp is welded to the reinforcementprofile P811.

The components are, for example, coordinated with one another and/ordimensioned such that the maximum tilting ΔKIPOF or the maximum angle ofthe tilting of the mold OF (corresponding to the angle between thetarget pressing direction ACHSOF* and the actual pressing directionACHSOF), as shown in FIG. 29 , is no greater than 10⁻²°, for example nogreater than 5·10⁻³°. Furthermore, it is provided that the radial offsetΔVEROF, i.e. the offset of the mold OF from its target position in thedirection orthogonal to the target pressing direction ACHSOF*, is nogreater than 50 μm, for example no greater than 30 μm, or no greaterthan 20 μm, or no greater than 10 μm.

The components are, for example, coordinated with one another and/ordimensioned such that the maximum tilting ΔKIPUF or the maximum angle ofthe tilting of the mold UF (corresponding to the angle between thetarget pressing direction ACHSUF* and the actual pressing directionACHSUF), as shown in FIG. 30 , is no greater than 10⁻²°, for example nogreater than 5·10⁻³°. Furthermore, it is provided that the radial offsetΔVERUF, i.e. the offset of the mold UF from its target position in thedirection orthogonal to the target pressing direction ACHSUF*, is nogreater than 50 μm, for example no greater than 30 μm, or no greaterthan 20 μm, or no greater than 10 μm.

Additionally or alternatively, it may be provided that the actuator O10is decoupled from torsion from the movable guide element O12 comprisingthe mold OF. In addition, it may be provided that the actuator U10 isalso decoupled from torsion from the mold-side movable connector U12together with the mold UF. FIG. 31 shows decoupling of this kind on thebasis of the example of decoupling the actuator O10 from the mold OFtogether with the movable guide element θ12. The decoupler, whichcomprises the ring ENTR and the discs ENTS1 and ENT2, prevents anytorsion from the actuator O10 acting on the mold OF.

The method described may also be carried out in connection with pressingunder vacuum or near vacuum or at least under negative pressure in achamber, as disclosed by way of example in JP 2003-048728 A. The methoddescribed may also be carried out in connection with pressing undervacuum or near vacuum or at least under negative pressure by means of abellows, as explained in the following on the basis of the pressingstation PS in FIG. 32 by way of example. In this case, it is providedthat a bellows BALG is provided or arranged between the movable guideelement O12 and the mold-side movable connector U12 for closing themolds OF and UF in an airtight manner or at least in a substantiallyairtight manner. Suitable methods are for example disclosed in theabove-mentioned JP 2003-048728 A (incorporated by reference in itsentirety) and in WO 2014/131426 A1 (incorporated by reference in itsentirety). In a corresponding configuration, a bellows may be provided,as disclosed in WO 2014/131426 A1, at least in a similar manner. It maybe provided that the pressing of an optical element, such as a headlightlens, is carried out by means of at least one lower mold UF and at leastone upper mold OF,

-   -   (a) wherein the heated preform or blank or gob 4001 (glass) is        placed in or on the lower mold UF,    -   (b) wherein (subsequently or thereafter) the upper mold OF and        the lower mold UF (are positioned relative to one another and)        are moved towards one another without the upper mold OF and the        lower mold UF forming a closed overall mold (for example far        enough that the distance (for example the vertical distance)        between the upper mold and the blank is no less than 4 mm and/or        no greater than 10 mm),    -   (c) wherein (subsequently or thereafter) the bellows BALG for        producing an airtight space, in which the upper mold OF and the        lower mold UF are arranged, is closed,    -   (d) wherein (subsequently or thereafter) a vacuum or near vacuum        or negative pressure is generated in the airtight space,    -   (e) wherein (subsequently or thereafter) the upper mold OF and        the lower mold UF are moved towards one another (for example        vertically) for (blank) pressing the optical lens element (for        example on both sides or all sides), wherein it is for example        provided that the upper mold OF and the lower mold UF contact        one another or form a closed overall mold (in this case, the        upper mold OF and the lower mold UF can be moved towards one        another such that the upper mold OF is moved (vertically)        towards the lower mold UF and/or the lower mold UF is moved        (vertically) towards the upper mold OF),    -   (f) wherein subsequently or thereafter normal pressure is        generated in the airtight space,    -   (g) wherein subsequently or thereafter, in another exemplary        configuration, the seal is opened or returned to its starting        position,    -   (h) and wherein subsequently or thereafter or during steps f)        and/or g), the upper mold OF and the lower mold UF are moved        away from one another.

In another exemplary configuration, before pressing the optical element,such as a headlight lens (or between step (d) and step (e)), apredetermined waiting time is allowed to elapse. In another exemplaryconfiguration, the predetermined waiting time is no greater than 3seconds (minus the duration of step (d)). In another exemplaryconfiguration, the predetermined waiting time is no less than 1 second(minus the duration of step (d)).

Following the pressing, the optical element (such as a headlight lens)is placed on a transport element 300 as shown in FIG. 7 by means of atransfer station 9. The annular transport element 300 shown in FIG. 7consists of steel, for example of ferritic steel or martensitic steel.The annular transport element 300 comprises, on its inner face, a(corresponding) support surface 302, on which the optical element to becooled, such as the headlight lens 202, is placed by its edge, such thatthe optical surfaces, such as the surface 205, are prevented from beingdamaged. Therefore, the (corresponding) support surface 302 and thesupport surface 261 of the lens edge 206 thus e.g. come into contact, asshown in FIG. 38 , for example. Here, FIGS. 10 and 38 show the fixingand orientation of the headlight lens 202 on the transport element 300by means of a limiting surface 305 or a limiting surface 306. Thelimiting surfaces 305 and 306 are orthogonal to the (corresponding)support surface 302, for example. In this case, it is provided that thelimiting surfaces 305, 306 have enough play relative to the headlightlens 202, such that the headlight lens 202 can be placed on thetransport element 300 for example without the headlight lens 202becoming tilted or jammed on the transport element 300.

FIG. 11 shows a transport element 3000 which is designed in analternative manner to the transport element 300 and is shown in FIG. 12in a cross-sectional view. Unless described otherwise, the transportelement 3000 is designed to be similar or identical/analogous to thetransport element 300. The transport element 3000 (likewise) compriseslimiting surfaces 3305 and 3306. In addition, a support surface 3302 isprovided, which, however, in a modification to the support surface 302,is designed to slant towards the midpoint of the transport element 3000.It is for example provided that the limiting surfaces 3305 and 3306 haveenough play relative to the headlight lens 202, wherein particularlyprecise orientation is achieved by the slope of the support surface3302. Moreover, the transport element 3000 is handled in an analogousmanner to the following description of the handling of the transportelement 300. The angle of the slant or slope of the support surface 3302relative to the orthogonal of the rotational axis or when used asintended relative to the support plane is between 5° and 20°, and in theembodiment shown is 10°.

In addition, before placing the headlight lens 202 on the transportelement 300, the transport element 300 is heated such that thetemperature of the transport element 300 is approximately +−50 K thetemperature of the headlight lens 202 or the edge 206. For example, theheating is carried out in a heating station 44 by means of an inductioncoil 320, as shown in FIGS. 8 and 9 . In these figures, the transportelement 300 is placed on a support 310 and for example is heated bymeans of the induction coil/induction heater 320 at a heating rate of30-50 K/s, for example in less than 10 seconds. The transport element300 is then grasped by a gripper 340, as shown in FIGS. 9 and 10 . Forthis purpose, the transport element 300 for example also has anindentation 304 on its outer edge, which is designed to becircumferential in one configuration. For correct orientation, thetransport element 300 comprises a marker slot 303. The transport element300 is guided to the press 8 by means of the gripper 340 and, as shownin FIG. 10 , the headlight lens 202 is transferred from the press 8 tothe transport element 300 and placed thereon.

In a suitable configuration, it is provided that the support 310 isdesigned as a rotatable plate. The transport element 300 is thus placedon the support 310 designed as a rotatable plate by hydraulic andautomated movement units (e.g. by means of the gripper 340). Centeringis then carried out by two centering jaws 341 and 342 of the gripper 340and specifically such that the transport elements are oriented in adefined manner by means of the marker slot 303, which is or can bedetected by means of a position sensor. Once this transport element 300has reached its linear end position, the support 340 designed as arotatable plate begins to rotate until a position sensor has detectedthe marker slot 303.

In a process step 126, an optical element or the headlight lens 202 ismoved through a surface-treatment station 45 according to FIG. 33 on thetransport element 300. In this figure, the optically active surface 204of the headlight lens 202 is sprayed with surface-treatment agent bymeans of a dual-substance nozzle 45 o and at least one optically activesurface of the optical element, such as the optically active surface 205of the headlight lens 202, is sprayed with surface-treatment agent bymeans of a dual-substance nozzle 45 u. The spraying process lasts nolonger than 12 seconds, for example no longer than 8 seconds, forexample no less than 2 seconds. The dual-substance nozzles 45 o and 45 ueach comprise an inlet for atomizing air and an inlet for liquid, inwhich the surface-treatment agent is supplied, which is converted into amist or spray mist by means of the atomizing air and exits through anozzle. In order to control the dual-substance nozzles 45 o and 45 u, acontrol air port is also provided, which is actuated by means of acontrol assembly 15 described in the following.

By means of the proposed method for producing an optical element or aheadlight lens, weather resistance and/or hydrolytic resistancecomparable to that of borosilicate glass is obtained. Furthermore, thecosts of the production process are only slightly higher than those ofthe production process for optical elements or headlight lenses havingweather resistance and/or hydrolytic resistance corresponding tosoda-lime glass.

The transport element 300 together with the headlight lens 202 is thenplaced on the annealing kiln 10. In a process step 127, the headlightlens 202 is cooled by means of the annealing kiln 10. FIG. 13 is adetailed schematic view of the exemplary annealing kiln 10 from FIG. 1 .The annealing kiln 10 comprises a tunnel which is or can be heated bymeans of a heating apparatus 52 and through which the headlight lenses202, 202′, 202″, 202′″ are moved slowly on transport elements 300, 300′,300″, 300′″ in the movement direction indicated by an arrow 50. In thisprocess, the heating power decreases in the movement direction of thetransport elements 300, 300′, 300″, 300′″ together with the headlightlenses 202, 202′, 202″, 202″. For moving the transport elements 300,300′, 300″, 300′″ together with the headlight lenses 202, 202′, 202″,202′″, a conveyor belt 51 is e.g. provided, for example made up of chainmembers or implemented as a series of rollers.

At the end of the annealing kiln 10, a removal station 11 is provided,which removes the transport element 300 together with the headlight lens202 from the annealing kiln 10. In addition, the removal station 11separates the transport element 300 and the headlight lens 202 andtransfers the transport element 300 to a return transport apparatus 43.From the return transport apparatus 43, the transport element 300 istransferred by means of the transfer station 9 to the heating station44, in which the transport element 300 is placed on the support 310designed as a rotatable plate and is heated by means of the inductionheater 320.

A process step 128 lastly follows, in which residues of thesurface-treatment agent on the lens are washed away in a washing station46.

It is for example provided that the optical element or lens has atransmission of greater than 90% after washing.

It may be provided that, with reference to the heating of a flat gob,microlens arrays are pressed, which are not used as an array, butinstead their individual lenses are used. An array of this kind is forexample shown in FIG. 54 , which shows a large number of individuallenses T50 on an array T 51, which have been generated by pressing. Insuch a case, it is provided that the individual lenses T 50 of the arrayT 51 are separated.

The device shown in FIG. 1 also comprises a control assembly 15 forcontrolling and/or regulating the device 1 shown in FIG. 1 . The device1A shown in FIG. 1A also comprises a control assembly 15A forcontrolling and/or regulating the device 1A shown in FIG. 1A. The device1B shown in FIG. 1B also comprises a control assembly 15B forcontrolling and/or regulating the device 1B shown in FIG. 1B. Thecontrol assemblies 15, 15A and 15B for example ensure that theindividual process steps are continuously interlinked.

The elements in FIGS. 1, 1A, 1B, 5, 6, 13, 24, 27, 28, 29, 30, 32, 33,34, 38, 39, 42, 43, 44 and 45, 46 , 47, 52, 53 and 54 are notnecessarily shown to scale for the sake of simplicity and clarity.Therefore, for example, the scales of some elements are exaggeratedcompared with other elements in order to improve the understanding ofthe embodiments of the present disclosure.

The claimed or disclosed method makes it possible to extend the scope ofapplication of press-molded lenses, for example in relation to objectivelenses, projection displays, microlens arrays and/or vehicle headlights,for example adaptive vehicle headlights.

LIST OF REFERENCE SIGNS

-   1, 1A, 1B device-   2 melting unit-   2B adjustable outlet-   3 preform device-   4, 4A, 4B transfer station-   5A, 5B, 5C cooling apparatuses-   6A, 6B, 6C heating apparatuses-   7 transfer station-   8 pressing station-   9 transfer station-   10 annealing kiln-   11 removal station-   15, 15A, 15B control assembly-   20 motor vehicle-   41 transport apparatus-   42 transport apparatus-   43 return transport apparatus-   44 heating station-   45 surface-treatment station-   45 o dual-substance nozzle-   45 u dual-substance nozzle-   46 washing station-   50 arrow-   51 conveyor belt-   52 heating apparatus-   120 process step-   121 process step-   122, 122′ process step-   123, 123′ process step-   124, 124′ process step-   125 process step-   126 process step-   127 process step-   128 process step-   130 preform-   131 temperature gradient-   132 temperature gradient-   201, 201′, 201″ motor-vehicle headlight-   202 headlight lens-   203 lens body-   204 substantially convex (for example optically active) surface-   205 substantially planar (for example optically active) surface-   206 lens edge-   210 light source-   212 reflector-   214 light stop-   215 edge-   220 cut-off line-   230 optical axis of 202-   260 step of 206-   261 surface of the lens edge 206-   300, 3000 transport element-   302, 3302 support surface-   303 marker slot-   304 indentation-   305, 3305 limiting surface-   306, 3306 limiting surface-   310 support-   320 induction coil/induction heater-   340 gripper-   341, 342 centering jaws-   400, 500 support devices-   401, 501 carrier body-   402, 502 support surface-   403, 503 base surface-   411, 511 flow channels-   412, 512 flow channels-   421, 521 metal filler material-   422, 522 metal filler material-   800 pressing station-   801 pressing unit-   802 pressing unit-   811, 812, 814, 815 rod-   816 upper connection part-   817 lower plate-   821 plate-   822 lower press mold-   823 upper press mold-   840 press drive-   841, 842, 843 rods-   850 press drive-   851, 852, 853 guide rod-   H851, H852, H853 sleeves-   L851, L853 bearing-   855 plate-   870 movement mechanism-   872 induction loop-   879 induction heater-   4001 gob-   4002 nut-   5000 hood-type annealing furnace-   5001 heating coil-   5002, 5202, 5302 protective cover-   5112, 5212, 5312 cylindrical region-   5132 rounded region-   5122, 5222, 5322 covering region-   5242, 5342 conical region-   5232, 5332 curvature-   DA diameter of 204-   DB diameter of 205-   DBq orthogonal diameter to DB-   DL diameter of 202-   DLq orthogonal diameter to DL-   F2 surround sensor system-   F3 controller-   F4 illumination device-   F5 objective lens-   F20, F201 vehicle headlight-   F41 light-source assembly-   F42 front optics-   F421 light exit surface of F4-   L4 light-   L41 light directed into F42-   L5 illumination pattern-   V1 front optics array-   V2 front optics-   V11, V12, V13, V14, V15 front optics-   V20 base part-   V21 surface of V20-   V111, V121, V131,-   V141, V151 light entry surface-   V115, V125, V135,-   V145, V155 side surfaces-   V2011, V2012, V2013,-   V2014, V2015 lenses-   V11-   VL light-source assembly-   M2 surround sensor system-   M3 controller-   M4 light-emission unit-   ML4 light-   M5 concave lens-   ML5 further-shaped light-   M6 projection optics-   ML6 resulting light distribution-   G20, M20 headlight-   G2 surround sensor system-   G3 controller-   G4 controller-   G5 illumination device-   GL5 light generated by GL5-   G6 system of micromirrors-   GL6 illumination pattern-   G7 projection optics-   GL7 light-   P_(max), P_(min) luminous power-   PS pressing station-   PO upper pressing unit-   PU lower pressing unit-   OF upper mold-   UF lower mold-   U10, O10 actuator-   U11, U12 movable connector-   U51, U52 movable guide rods-   UO fixed guide element-   O11 actuator-side connector-   O12 movable guide element-   O14 mold-side connector-   O51, O52 fixed guide rods-   P811, P812 reinforcement profile-   SP811, SP812,-   SP814, SP815 clamps-   ΔKIPOF, ΔKIPUF maximum tilting-   ACHSOF, ACHSUF actual pressing direction-   ACHSOF*, ACHSUF* target pressing direction-   ΔVEROF, ΔVERUF-   ENTR ring-   ENTS1, ENTS2 discs-   BALG bellows-   T1 preform-   T2, T3 clamping devices-   T4 clamping assembly

The invention claimed is:
 1. A method of producing a headlight lens, themethod comprising: heating a blank made of soda-lime glass; providing asurface-treatment agent which comprises a solvent and a solid dissolvedin the solvent, wherein the solid comprises at least one solid from thegroup consisting of aluminum, aluminum chloride, aqueous aluminumchloride, aluminum salt, fatty-acid aluminum salts, phosphate, potassiumphosphate, sodium phosphate, KO₂, KOH, KNO₃, silicate, SiO₂, potassiumsilicate and potassium; providing a gas; generating a spray mist bythoroughly mixing the surface-treatment agent with the gas; providing afirst mold; providing at least a second mold; providing a cooling path;press-molding the heated blank to form a headlight lens having at leasta first optically active surface by means of the first mold and the atleast a second mold; spraying the at least first optically activesurface with the spray mist; and cooling the headlight lens inaccordance with a cooling regime in the cooling path by adding heat. 2.The method according to claim 1, wherein the solid comprises fatty-acidaluminum salts.
 3. The method according to claim 1, wherein the solidcomprises phosphate.
 4. The method according to claim 1, wherein the gascomprises compressed air.
 5. The method according to claim 4, whereinthe surface-treatment agent comprises, based on the total mass of thesurface-treatment agent, 25 to 65 wt. % water, 30 to 70 wt. % potassiumphosphate, 1 to 8 wt. % sodium phosphate and 0.001 to 0.010 wt. %aluminum, wherein the constituents do not add up to more than 100%. 6.The method according to claim 4, wherein the surface-treatment agentcomprises, based on the total mass of the surface-treatment agent, 25 to65 wt. % water.
 7. The method according to claim 4, wherein thesurface-treatment agent comprises, based on the total mass of thesurface-treatment agent, 30 to 70 wt. % potassium phosphate.
 8. Themethod according to claim 4, wherein the temperature of the opticallyactive surface during spraying with surface-treatment agent is no lessthan TG and no greater than TG+150 K, wherein TG denotes the glasstransition temperature.
 9. The method according to claim 4, wherein thetemperature of the optically active surface during spraying withsurface-treatment agent is no less than TG+20 K and no greater thanTG+150 K, wherein TG denotes the glass transition temperature.
 10. Themethod according to claim 1, wherein the surface-treatment agentcomprises, based on the total mass of the surface-treatment agent, 25 to65 wt. % water, 30 to 70 wt. % potassium phosphate, 1 to 8 wt. % sodiumphosphate and 0.001 to 0.010 wt. % aluminum, wherein the constituents donot add up to more than 100%.
 11. The method according to claim 1,wherein the surface-treatment agent comprises, based on the total massof the surface-treatment agent, 25 to 65 wt. % water.
 12. The methodaccording to claim 11, wherein the temperature of the optically activesurface during spraying with surface-treatment agent is no less than TGand no greater than TG+150 K, wherein TG denotes the glass transitiontemperature of the soda-lime glass.
 13. The method according to claim11, wherein the temperature of the optically active surface duringspraying with surface-treatment agent is no less than TG+20 K and nogreater than TG+150 K, wherein TG denotes the glass transitiontemperature of the soda-lime glass.
 14. The method according to claim 1,wherein the surface-treatment agent comprises, based on the total massof the surface-treatment agent, 30 to 70 wt. % potassium phosphate. 15.A method of producing a headlight lens, the method comprising: providinga heated blank made of soda-lime glass; providing a solvent; providing asolid; providing a gas; dissolving the solid in the solvent; thengenerating a sulfur-comprising spray mist by thoroughly mixing thesolvent with the gas; providing a first mold; providing at least asecond mold; providing a cooling path; press-molding the heated blank toform a headlight lens having at least a first optically active surfaceusing the first mold and the at least second mold; spraying the firstoptically active surface with the spray mist; and cooling the headlightlens in accordance with a cooling regime in the cooling path withaddition of heat.
 16. The method according to claim 15, wherein thesurface-treatment agent comprises water.
 17. The method according toclaim 15, wherein the surface-treatment agent comprises, based on thetotal mass of the surface-treatment agent, 25 to 65 wt. % water.
 18. Themethod according to claim 17, wherein the temperature of the opticallyactive surface during spraying with surface-treatment agent is no lessthan TG+20 K and no greater than TG+150 K, wherein TG denotes the glasstransition temperature of the soda-lime glass.
 19. The method accordingto claim 18, wherein the surface-treatment agent forms droplets, ofwhich the average diameter is no greater than 50 μm.
 20. The methodaccording to claim 19, wherein the optically active surface is sprayedfor no longer than 4 seconds.
 21. A method of producing an opticalelement, the method comprising: heating a blank made of glass; providinga surface-treatment agent which comprises a solvent and a soliddissolved in the solvent, wherein the solid comprises at least one solidfrom the group consisting of fatty-acid aluminum salts and phosphate;providing compressed air; providing a mixing nozzle; generating a spraymist using the mixing nozzle to mix the surface-treatment agent with thecompressed air; providing a first mold; providing at least a secondmold; press-molding the heated blank to form an optical element having afirst optically active surface using the first mold and the at leastsecond mold; spraying the at least first optically active surface withthe spray mist; and cooling the optical element in accordance with acooling regime with addition of heat.
 22. The method according to claim21, wherein the temperature of the optically active surface duringspraying with surface-treatment agent is no less than TG+20 K and nogreater than TG+150 K, wherein TG denotes the glass transitiontemperature of the glass.
 23. The method according to claim 22, whereinthe surface-treatment agent comprises, based on the total mass of thesurface-treatment agent, 25 to 65 wt. % water, 30 to 70 wt. % potassiumphosphate, 1 to 8 wt. % sodium phosphate and 0.001 to 0.010 wt. %aluminum, wherein the constituents do not add up to more than 100%. 24.The method according to claim 22, wherein the surface-treatment agentcomprises, based on the total mass of the surface-treatment agent, 25 to65 wt. % water.
 25. The method according to claim 22, wherein thesurface-treatment agent comprises, based on the total mass of thesurface-treatment agent, 30 to 70 wt. % potassium phosphate.
 26. Themethod according to claim 23, wherein the surface-treatment agent formsdroplets in the spray mist, of which the average diameter is no greaterthan 50 μm.
 27. The method according to claim 26, wherein the opticallyactive surface is sprayed for no longer than 4 seconds.
 28. The methodaccording to claim 21, wherein the solid comprises fatty-acid aluminumsalts.